Suma is a Membership and Subscription Management plug-in for the WordPress publishing system. It provides functionality that transforms WordPress into a pay-to-view, membership-oriented, subscription-based content publishing platform.
With Suma, you can restrict access to particular pages and posts of your website. Visitors to your website who don’t have a subscription will then only see the title and excerpt of those posts and pages. If the visitor subscribes, then they are given instant access to the content.